1. Field of the Invention
This invention relates to magnetic tape recorder drive mechanisms.
2. Description of the Prior Art
Magnetic tape recorders suitable for voice logging use are often voice activated to save tape and to reduce the frequency with which tapes must be changed. A major problem of such voice activated recorders has been the inability to capture the first portion of a message due to the time required to bring the tape to full operating speed. Such a portion may contain vital information such as the first digit of a number or the name of a person to whom the conversation is being directed. In the so called "Watergate tapes", important information was often lost before the recorder became fully operative.
Typically, voice activated logging recorders employ electrical solenoids to switch from standby into run position. Approximately 100 milliseconds may be required. While it might be possible to reduce the switching time by employing larger solenoids or by driving the solenoids with larger current pulses, this would be tend to increase the expense and size of the recorders.